Abbott: Stent Tops Rival Device In Three-Year Study
30 March 2009 - 1:12AM
Dow Jones News
Three-year data from a study on Abbott Laboratories' (ABT)
"Xience" heart stent showed it performed better on certain measures
than a Boston Scientific Corp. (BSX) stent, according to details
Abbott released Sunday.
Xience is already the top-selling drug-coated stent in the U.S.
and Europe behind earlier data showing it outperformed Boston
Scientific's "Taxus" devices, so the latest data from the
300-patient Spirit II study - which showed a widened performance
gap over the last year - appear unlikely to alter trends in the $4
billion global market for the devices.
But the new data, released at the American College of
Cardiology's annual conference, do create a longer-term performance
measure for Abbott's device. The data release also marks an
opportunity for doctors and Wall Street analysts to see how Xience
performed between years two and three, after data from the two-year
mark raised some questions about narrowing in the arteries of
Xience-treated patients.
Measuring that narrowing at the six-month mark was the
Abbott-sponsored study's original main goal.
Johnson & Johnson (JNJ) and Medtronic Inc. (MDT) also make
coated stents, which are tiny scaffolds for heart arteries that use
medication to fight the growth of scar tissue that can lead to
repeat procedures.
Boston Scientific also benefits from good Xience data because it
sells a version of the stent, called Promus, and then shares
profits with Abbott under a deal connected to an acquisition three
years ago.
Patients in the Spirit II trial were randomized so that three
people had a Xience stent for every one who had a Taxus. At three
years, there was a 6.4% rate of so-called "major adverse cardiac
events" among Xience patients and a 14.9% rate among Taxus
patients, with the difference considered statistically significant,
according to Abbott.
The major events measure is a combination of cardiac death,
heart attacks or re-treatment of the same area due to lack of blood
supply to the heart. This rate for Xience was the same between
years two and three but increased for Taxus.
The Spirit II study, which included patients outside the U.S.,
mainly used an older version of Boston Scientific's Taxus device,
although some patients were treated with a newer version the
company sells called Taxus Liberte.
Among individual events, the reduced risk of cardiac death among
Xience patients was also considered statistically significant,
while the lower percentage rates of heart attacks and re-treatment
for Xience patients were not considered statistically
significant.
When two-year data were released last year, analysis of a subset
of patients who had their arteries imaged with an angiogram showed
Abbott's stent lost its early edge on a measure called "late loss,"
or narrowing in the stented area.
This type of analysis was not performed again at the three-year
mark, making the latest trends there unclear. But the rate of
events with the devices can offer clues about whether the narrowing
led to problems. John Capek, executive vice president of medical
devices at Abbott, noted in an interview that clinical events have
grown faster in the Taxus arm than in the Xience arm.
-By Jon Kamp, Dow Jones Newswires; 617-654-6728;
jon.kamp@dowjones.com